Plaster lath



Feb. 1925- 1,524,938

J. F. MAKOWSKI LLLLLLLLL TH INVENTOR.

John E Makowski/ A TTORNEY I [Patented Feb. 3, 1925.

UNITED STATES 1,524,938 PATENT oFFIce.

JOHN F. MAKOWSKI, OF STOCKTON, CALIFORNIA, ASSIGNOR '10 GALIEORNIA CEDAR PRODUCTS COMPANY, OF STOCKTON, CALIFORNIA.

PLASTER LATH.

Application filed November 7, 1923. Serial No. 673,234.

' To all whom it may concern:

Be it known that I, J 01m F. MAKowsK a' citizen of the United States, residing at Stockton, county of San Joaquin, State of 5 California, have invented certain new and useful Improvements in Plaster Laths; and I do declare the following to be a full,' clear,* and exact description of thesarhe, reference being. bad to the accompanying drawings, and tothe characters of reference marked thereon, which form a part of this apphcation.

This invention relates to the building art and particularly to wall construction.

The object of the invention is to produce a plaster lath built upon a plaster board base of such'strength as to best sustain the strains and stresses of the weight of" the plaster and to form on the .face of the plaster board a continuous mechanical key surface for adhering the plaster thereto. This type of plaster lath per so has been heretofore produced by me and the present invention relates specifically to the elementary construction'or make-up of the lath and particularly the "s ecific lamination or coating material use to adhere the mechanical key face to the plaster board base. After many years of study and experiment'and a trial production in this art. I have ascertained that to produce a commercially successful plaster board of this type it is essential that this lamination must be fire and moisture resistant to the highest possible degree and as in. addition thereto it must have very in terlise adhesive qualities in order to proper an plaster thereon.

Summing vupther efore a successful lath 40 of this type, must in its combination consist first of a strong nonpeeling plaster board for a base, and second must have its key surface strongly adhered to the base with a substantially fire'and moisture proof lamination between the two. Failure to have both of these essentials renders the product non-commercial.

I have therefore produced a lath. made u in detail ashereinafter set forth an as claimed, which detailed composition attains the objects of the invention.

The figure-in the drawings is a cross see- I I tional view of the plaster lath.

The base sheet or body of the lath is a preferably up of what is hown-as sustain the weight of the key surface.

plaster board of that type inwhich plastic material 1 is introduced between two surfacelpaper sheets 2 and 3 which, when the plastic material dries, is thoroughly adhered thereto. In using such a base for the support for the mechanical key or bond of the lath, the tenacity of this adhesive becomes a very decided factor in the 'produc tion of a commerically successful lath. 4

Therefore the type of plaster board specifically shown and described in my co-pending application for patent, Serial No.

536,350, through the use of the adhesive dextrin as set forth therein, has provided the necessary tenacious adherence both for the mass and the surface sheets so that peelers are eliminated and the plaster key or bond surface may be safely used thereon, as there is no danger of the weight of the plaster pulling the sheets loose or sagging the board in any way.

Having found a suitable base for the lath my next problem was to provide the proper adhesive for cementing the mechanical key or bonding surface to the base support. Fire underwriters rules require that the lath meet theirspecifications and the trade demands that the lath, especially; for exnally enabled me to determine that a cementitious composition made up of magnesite, with :silicyl as afiller and magnesium chloride, to'cause the composition to harden and set, substantially satisfies all requirements as above enumerated. I

The magnesite could be used alone without the body or carrier material but the latter is added in order to kee the cost of the product as low as possib e.

I use generally b bulk, one part magnesite, one and one alf arts. nineteen. per cent (Baum) solution of magnesium'chloe ride and two parts diatomaceous, earth.

This is applied to the surface of the ture while at the same time furnishing the eat adhesive qualities required.

When the magnesite composition is aplied to the base board the chloride soaks into the paper surface and this tends to fireproof the paper per se.

- In the completed lath the wall board forms the base or body thereof the magnesite composition forms the water and fire proofing element and the adhesive in which is formed the mechanical key or bond, which latter in turn forms the key surface to which the plaster is to be adhered.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is:

1. A plaster lath comprising a base, a surface lamination of fire and water resisting composition on the base, such composition consisting of magnesite and silicyl mixed with magnesium chloride; and a mechanical plaster key surface adhered to the base through the medium of such composition.

2. A plaster lath comprising a plastic base having a paper sheet adhered thereto, and a mechanical plaster key adhered to the sheet through the medium of a composition consisting-essentially of magnesite and magnesium chloride.

3. A plaster lath comprising a base. a coating on the base in which magnesite mixed with magnesium chloride is the es sential element, and a plaster key adhered to such coating. 1

4. A plaster lath comprising a base, a composition coating having magnesite mixed with magnesium spread over the surface of the base, and a plaster key surface formed in the composition.

5. A plaster lath comprising a base, a surface lamination of fire and water resisting composition on the base, such composition consisting of magnesite and diatomaceous earth mixed with magnesium chloride; and a mechanical plaster key surface adhered to the base through the medium of such composition.

6. A plaster lath comprising a base, a composition coating having magnesite mixed with magnesium chloride therein spread over the surface of the base, and a mechanical plaster key surface adhered ..to the base through the medium of said composition.

In testlmony whereof I aflix my signature.

JOHN F. MAKOWSKI.

chloride therein 

